Hello arsya240,
Welcome to Apple Support Communities.
We understand that you’re getting an error when trying to add your boarding pass to Wallet. We are happy to help.
We do show recent maintenance and upcoming maintenance for Apple Pay and Wallet here: Apple - Support - System Status
We recommend trying these steps to add your boarding pass: Add, use, and share boarding passes, tickets, and other passes in Apple Wallet - Apple Support
"How to add a boarding pass, ticket, or other pass to Apple Wallet on your iPhone
- Open the app, email, notification, or other communication that contains your boarding pass, ticket, or other pass.
- Tap Add to Apple Wallet.

3. Follow the instructions on the screen.
4. If necessary, tap Add in the upper right corner.
If you don't see an option to add your boarding pass, ticket, or other pass to the Wallet app, contact the merchant or company that issued it to make sure they support passes in the Wallet app.
When you add a boarding pass, ticket, or other pass to the Wallet app on your iPhone, you automatically add it to the Wallet app on your paired Apple Watch.
Learn how to remove a pass or ticket from the Wallet app."
These steps may help. Let us know if you have further questions.
Take care.